Sustainable Building System

ABSTRACT

The disclosure relates to a sustainable building system (SBS) that is affordable, capable of being replicated at a small and large scale, significantly reduces both the heating and cooling loads of the building as well as the total energy that the building consumes. Energy consumption can be reduced sufficiently that the building is capable of net-zero-energy status. That is, a building made using the system, method and components described herein can, with the inclusion of appropriate renewable energy technologies, generate on site all the energy that the building needs. Specific to this SBS is the design of a super-insulated and nearly air-tight building thermal envelop, that is, to the greatest extent possible, thermal-bridge-free and that has incorporated into that envelope high performance windows and doors.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is entitled to priority to U.S. provisional patentapplication 61793,797, filed 15 Mar. 2013, which is incorporated hereinby reference in its entirety.

BACKGROUND OF THE INVENTION

Others have described a Passive House Standard, which is a buildingstandard developed by the International Passive liotise in Darmstadt,Germany, founded by Dr. Wolfgang Fiest, and Passive House Institute US,developed by founder Katrin Klingenberg, Ohio. That standard has threerequirements: (i) a maximum projected Heating and Cooling load of 4.75thousand British Thermal Units per square foot per year (kBTU/sf/year);(ii) a maximum Total Energy demand of 38 kBTU/sf/year; and a maximummeasured air-tightness of 0.6 air changes per hour (ACH) at 50 Pascalsof pressure.

The context for the subject matter described herein involves what thePassive House Standard refers to as a “Fabric First” approach tobuilding science and the design of high-performance and net-zero-energybuildings. This means that if one focuses on the “fabric” of thebuilding first, i.e., the thermal envelop, rather than the technologicalmachines within that thermal envelope that produce heating, cooling,lighting, hot water and ventilation more or less efficiently, and if onefocuses on designing that thermal_(—) envelop as a super-insulated andair-tight “fabric” or “coat” for the building, then one can reduce theheating and cooling requirements or loads by up to 90% of what a typical“code compliant” building requires. Second, if one designs that “fabric”as a super-insulated and air-tight thermal envelop, the heating,ventilation and air conditioning systems get significantly smaller (astheir ‘loads’ can be roughly one ninth of a typical code compliantbuilding), more efficient and therefore significantly higher performing.Similarly domestic hot water, lighting, and appliance systems can alsodesigned as extremely efficient and integral instruments of a buildingsystem. If one reduces a building's energy requirement by up to 90%,then the remaining 10% of energy needed for that building can be readilymet with a relatively small amount of on-site renewable energygeneration in several forms (photovoltaic power, solar thermal heat,geothermal hydronic heating and cooling, or the like), allowingbuildings to achieve net-zero-energy or net-positive-energy status.

The subject matter disclosed herein provides buildings, buildingcomponents, and methods of making buildings that yield structures havingsignificantly reduced energy requirements.

BRIEF SUMMARY OF THE DISCLOSURE

This disclosure relates to a system for modular assembly of a building.The system includes a plurality of building modules including aplurality of outer building modules (i.e., modules which include asurface which ultimately becomes a portion of the exterior surface ofthe assembled building). The system also includes an envelope patch forsealing gaps between the modules to exclude airflow from passing betweenthe modules. Each of the outer building modules has an envelope materialon the portion of the building's exterior face that occurs on themodule. After the modules are assembled to form the building, gapsbetween the envelope materials on the various modules are sealed usingthe envelope patch, thereby creating a substantially non-perforatedenvelope that blankets the building exclusive of doors, windows, andutility openings. In those openings, precautions are taken (e.g., highefficiency doors and windows and careful insulation of unused portionsof utility openings) to minimize energy loss. These characteristics,together with selection of appropriate insulating materials in thestructural elements of the modules, result in an energy-efficientbuilding that can satisfy the Passive House standards and that can, withthe installation of energy-generating elements such as solar panels,result in a net-zero- or net-positive-energy building.

An important component of the building and modules described herein isan energy-conserving air exchanger and ventilator combination that canbe assembled with the building modules to form the building. This systemtransfers heat energy between interior air being exhausted from thebuilding and exterior air being drawn into the building for ventilation.This system can significantly reduce the energy required to heat or coolthe interior of the building,

Another important component of the building and modules described hereinis an energy monitoring system that can be operably assembled with thebuilding modules to permit monitoring of energy use within the assembledbuilding. The energy monitoring system permits a person (or an automatedsystem directed by a person) to identify sources of energy use withinthe building and to adjust the building or As characteristics tomodulate energy use.

An important characteristic of the building system is its modularity andcorresponding transportability. Each building module can be designed tobe shippable by any desired means, such as by truck on local roads orinterstate highways. Thus, the building modules can be designed to havespecified or not-to-exceed dimensions, such as a height not greater than12 feet, a length not greater than 70 feet, and a width not greater than16 feet.

The building modules can be manufactured at a location distant from thedesired site of building construction, shipped to the site, and thereassembled.

DETAILED DESCRIPTION

The disclosure relates to a sustainable building system (SBS) that isaffordable, capable of being replicated at a small and large scale,significantly reduces both the heating and cooling loads of the buildingas well as the total energy that the building consumes. Energyconsumption can be reduced sufficiently that the building is capable ofnet-zero-energy status. That is, a building made using the system,method and components described herein can, with the inclusion ofappropriate renewable energy technologies, generate on site all theenergy that the building needs. Specific to this SBS is the design of asuper-insulated and nearly air-tight building thermal envelop, that is,to the greatest extent possible, thermal-bridge-free and that hasincorporated into that envelope high performance windows and doors.

The design of this super insulated and nearly air-tight thermal envelopand building technology system also incorporates low energy heating,cooling and energy recovery ventilation systems, as well as low energylighting systems, appliances, domestic hot water systems and energymonitoring systems. This building technology is designed such that itcan be built in a modular building factory, built via “panelized”pre-fabricated method, as well as site or “stick-built”.

The present invention is related to the design and construction ofbuildings that are affordable, considered “high-performance” and havethe ability to reach Net-Zero-Energy status. What is unique about thisinvention is that our Sustainable Building System (SBS) is designed towork with conventional building materials, technologies and practices,and designed to be built with a conventional workforce with limitedtraining The significant invention of our SES involves HOW we put theseconventional materials together, how the details are designed such thatthere is limited thermal-bridging between inside and outside within thethermal envelop and limited “punctures” or openings between the insideand the outside of a building.

The sustainable building system (SBS) described herein is made up of thefollowing components. At a macro scale, the building modules areconceptualized as cells of built space rather than individual,self-contained objects, allowing the modules, or boxes, to be assembledin infinite configurations to accommodate various architectural designs.This necessitates the need to air seal each module to the next, on site,to maintain a continuous air seal and thermal envelope across allexterior walls of the building enclosure.

Energy Envelope Design

The design of the total assembly of modules, panels, or site builtmaterials which make up the building is initially designed utilizingenergy modeling software developed by the Passive House Institute todetermine the minimal amount of insulation required, both in the wallsand on the exterior, based on the building's geographical location,specific orientation to the sun to eliminate thermal transfer throughthe building envelope necessary to achieve the Passive Housecertification metrics noted above. The energy envelope in conjunctionwith the building's mechanical system design, energy efficient applianceand lighting forms the holistic details of the Sustainable BuildingSystem.

The Individual Module Envelope

At a micro level, the individual module has been detailed to utilizestandard 2×4/2×6 wood frame construction (or other equivalentconstruction, such as metal stud frame construction) to allow areasonably skilled carpenter or other builder to build the framework forthe building envelope described herein. The walls, ground floor and roofstructures are filled with and insulating material such as dense packedcellulose insulation, or a “spray and batt” insulation system whichutilizes a layer of closed cell spray foam insulation on the interior ofthe wall against the backside of the sheathing, with the balance of theframed cavity filled with, for example, standard fiberglass battinsulation.

Exterior Sheathing with an integral water resistant barrier is utilized,which serves as both the moisture barrier as well as the air barrier tothe This membrane is placed on the exterior of the framed walls andbelow the lowest floor module to maintain a continuous air barrier. Alljoints, junctures in the walls of the modules and limited penetrationsin the exterior walls are air-sealed with a bituminous tape or anotherairflow-occluding material. Similarly, the roof sheathing joints arefully taped. Incorporation of airtight, triple glazed windows and doorsare placed so that the exterior surface of these units are placed flushwith the sheathing allowing easy air tape sealing of the windows, doors,door thresholds to the sheathing air barrier. All gaps between thewindows and door units and the rough framed opening are filledcompletely with spray foam insulation (or other insulation) and acompressible seal (or other gap-occluding apparatus s used under thedoor threshold. The interior walls are finished in typical gypsum boardconstruction (or other interior finishing material), and a supplementalchase wall or “utility base board” chase can be added to allow for therunning of pipes and wires, and the placement of junction boxes withoutpenetrating the exterior thermal wall enveloped.

The exterior of the sheathing is covered in rigid expanded styreneinsulation (XPS) following the taping of all seams. This insulation isrun continuously up the walls and under the roof system prior to theparapet walls being anchored through the insulation in order to maintainthe thermal bridge free construction. Similarly, the underside of thelowest modules are skinned in air seal taped, air-tight sheathing andXPS insulation, whether the design calls for a basement, crawl space oron grade application to prevent thermal and air penetration from below.ALL joints in the XPS is then tape and sealed with a foil faced tape toprovide an additional layer of air sealing to the envelope. All jointsof XPS and sheathing are installed on a “staggered” pattern. All utilitypenetrations and ductwork from below are fully air seated at thepenetration point of the thermal envelope, and all ductwork outside theenvelope is insulated and treated as an exterior wall thermal envelopeto prevent condensation and thermal transfer into the structure. Therigid exterior insulation thickness is detailed in order to insure thatthe dew point of the wall falls outside the exterior sheathing to avoidmoisture within the framed

Rain Screen Construction

Outboard of the XPS insulation, the walls are furred out with ¾″material (preferably, other thicknesses can be used, of course),anchored to the individual wall frame studs, to create a ventilatedcavity which allows any moisture which enters through the building skinto have a path back out. This keeps the majority of all water away fromthe moisture resistant sheathing.

Green Roof System Option

The top floor module is structurally engineered to support the saturatedweight of an extensive or intensive green roof system. The green roofcan be physically assembled, including vegetation, in the modularfactory so that the system is complete when the top module is placed onsite, or done on site. Modular Factory installation takes advantage ofthe fact that a crane is already on site hoisting the modules, andtherefore eliminates the added crane cost and staging requirements tofield build the green roof after the building has been assembled; thusfurther reducing overall building costs. This option is critical toallow for additional green space for the structure, but also to providea system that meets stormwater management regulations in variousmunicipalities.

The air tight, well-insulated, thermal bridge free construction reducesthe energy consumption of the building by up to 90% because thermaltransfer is effectively eliminated keeping the heat in in the winter andthe cooling in in the summer months, paired with energy efficientmechanical systems, lighting and appliances. As a result, the building'sprimary energy source is completely electric, eliminating natural gasfrom the building. This dramatically reduces construction costs byeliminating the introduction of another utility into the building andall associated ventilation requirements for combustible gas systems, andthe needed penetrations in the exterior envelope for these exhaustcomponents “although natural gas applications are also acceptable.

Mechanical Systems

A unique portion of our sustainable building system is the design of theheating, ventilation and air conditioning system (HVAC). Given therequirements of our SBS air-tightness levels, mechanical fresh airventilation is required for any SBS structure. That mechanicalventilation must bring in fresh air to the building, exhaust stale airfrom the building and minimize energy tosses in the process. This isachieved by using either an Energy Recovery Ventilator (ERV) or a HeatRecovery Ventilator (HRV) and must have efficiencies of at least 75%.These devices include a heat-energy-exchanger and a ventilator toconserve interior heating or cooling by exchanging energy betweeninterior air being exhausted and exterior air being drawn in.

Given the very low heating and cooling demands of these buildings builtwith our SBS, a single device that delivers a very low amount of heatingand cooling combined with an

ERV or HRV is not commercially available in the United States. We haveachieved a HVAC system designed for our SBS that meets this need bycombining an off-the-shelf General Electric Zoneline brand (orequivalent) PTAC (Packaged Terminal Air Conditioner) air-sourced heatpump, with an off-the-shelf Ultimate Aire brand ERV (or an equivalent)to create an efficient HVAC system that meets the needs of the towenergy heating and cooling demands of our SBS and the ventilationrequirements.

The PTAC unit is designed to be a “through-wall” heat pump (typicallyused in hotels, student dorms, office buildings) whereby one of thecoils of the heat pump is directly exposed to the exterior and the othercoil of the heat pump is exposed to the interior of the building (i.e.,it is within the thermal envelope). Our design for this PTAC involvesmoving the entire packaged heat pump unit within the thermal envelope,carefully and significantly insulating the duct work on both the freshair intake and exhaust side of the heat pump within the thermal envelop,thereby being able to significantly reduce the heat losses inherent tothe typical “through-wall” design of the heat pump. This is an importantimprovement in the design and performance of this off-the-shelf heatpump. A second improvement occurs when the duct work of the ERV isconnected to the ductwork of the heat pump.

The exhaust side of the ERV connects directly to the fresh air intakeside of the outside coil of the heat pump, but only after a damper.Exhaust from the ERV passes over the outside coil of the heat pumpbefore it is exhausted to the exterior. In so doing, the exhaustelevates the temperature of the incoming air, in the winter, lowers itin the summer, and in the process increases the coefficient ofperformance (COP) of the heat pump, as the COP is entirely dependent onthe ambient temperature of the exterior going across the outside coilThis “marrying” of the ERV and the PTAC heat pump increases theperformance of the heat pump, helping it run at a higher COP regardlessof the exterior temperature. This would not be possible for the PTACheat pump in its originally designed state.

Another important feature of this HVAC design for our SBS systeminvolves a bypass damper, mechanically controlled and linked totemperature sensors inside and outside the thermal envelop. Forinstance, if the interior temperature is significantly higher than theexterior temperature, the ERV will turn off, as well as the compressorson the heat pump, and the damper will open, fans in the ERV will turn onand fresh air will be brought in directly to the supply side of the ductwork inside the thermal envelope, lowering the temperature of theinterior solely without the need for mechanical cooling.

In general, the design of our HVAC system within our SBS is unique,specific to the very particular heating, cooling and ventilationrequirements of a nearly air-tight envelope of a

Passive House structure and uses off-the-shelf components in a mannerwhich has not been done before.

Energy Monitoring

The buildings made as described herein can be equipped with energymonitoring devices tied to each of the electrical circuit breakers, andany renewable energy source, to track and collect data on theconsumption and production side of the systems. Additionally, roomsensors are placed through the building to measure, temperature, airquality (CO2 levels), and humidity to inform the mechanical systems andmeasure these critical values. Remote and on-site monitoring providesthe occupant real time data to alter their usage of the building toincrease their energy performance, while also enabling the engineers,legislators and maintenance personnel critical data about theperformance of the SBS. Those access to the system, can also altertemperature settings remotely.

Placement of the Modules—Maintaining Air Tight Construction BetweenComponents:

Air Sealing

Each module is placed on top of the next in vertical stacks. The firststack, which is accessible from both sides is mechanically secured toone another utilizing mechanical strap fasteners which are in turn airsealed with bituminous tape, and the horizontal joints between eachmodule are also air sealed with bituminous tape. In placing the secondadjacent module stack, the first base module is placed and the top plateof the newly placed box is tape sealed to the adjacent (first stack) boxas an inside corner detail in order to seal the two boxes togetherhorizontally. Prior to setting the subsequent module in the secondstack, two side by side layers of expanding foam tape or gasketingmaterial (or any equivalent expanding or expandable material) is placedon the same top plate to form a horizontal airtight seal between the twovertically placed boxes. Thus, inter-module gaps are both filled withthe expanding material and sealed with a metal-faced or bituminous tape,reducing or eliminating air infiltration from the exterior of theresulting building and the spaces between the modules. The other threesides of the newly placed module stack remain exposed and accessible toinstall the standard horizontal bituminous taped seam.

The above stated sequence is repeated for each new vertical andhorizontal placement of modules as the building expands.

Hoisting

In order to avoid penetrations in the exterior envelope of the modules,a key restriction in air-tight construction, a modified hoisting methodhas been designed. Centered on the thickness of the exterior walls ofeach module, within the floor framing cavity, a steel bracket with aconnector nut is lag bolted into the floor structure at the quarterpoints of the module's long walls. A continuous piece of ElectricalMetal Tubing (EMT) is placed vertically in the exterior module walls intine with the connector nut and run up through the top plates of the boxconstruction. Removable threaded steel rods with eye bolts on the end toconnect to the Crane spreader bar. The EMT is placed to maintainalignment to the base nut and a conduit for the steel rods to penetratethe wall insulation. After hoisting the modules, the rods are removedand re-used on the next lift. The remaining hole is filled with sprayfoam insulation and taped with air seal tape. This solution modifies themore typical approach in which holes are placed in the lower side wallof the module, within the floor framing, and a removable steel hoistcable is run through the box. After the module is in placed with thetraditional method, there is no way to seal these holes after the fact.

It is a goal of the subject matter described herein to provide tobuilders, developers, politicians, institutions, building manufacturers,modular building manufacturers, panelized building componentmanufacturers, homeowners and the general public an affordable andhigh-performance, net-zero-energy-capable and sustainable buildingsystem that would significantly increase the design and energy codes andstandards by which new buildings are to be conceived and built;significantly reducing the energy that buildings consume andsignificantly reducing the carbon dioxide emissions that come from themaking and operating of buildings.

The disclosure of every patent, patent application, and publicationcited herein is hereby incorporated herein by reference in its entirety.

While this subject matter has been disclosed with reference to specificembodiments, it is apparent that other embodiments and variations can bedevised by others skilled in the art without departing from the truespirit and scope of the subject matter described herein. The appendedclaims include all such embodiments and equivalent variations.

What is claimed is:
 1. A system for modular assembly of a building, thesystem comprising a plurality of building modules including a pluralityof outer building modules and an envelope patch, each of the outerbuilding modules including at least one exterior face having a portionof an envelope as a component of the exterior face, the building modulesbeing assemblable to form a building having the envelope on the exteriorfaces thereof, and including sufficient envelope patch to bridge theinter-module gaps in the envelope.
 2. The system of claim 1, furtherincluding an energy-conserving air exchanger and ventilator that can beassembled with the building modules to form the building.
 3. The systemof claim 1, further comprising an energy monitoring system that can beoperably assembled with the building modules to permit monitoring ofenergy use within the assembled building.
 4. The system of claim 1,wherein each building module has shipping dimensions wherein its heightis not greater than 12 feet, its length is not greater than 70 feet, andits width is not greater than 16 feet.
 5. The system of claim 4, whereinthe shipping dimensions does not include the vehicle used for shippingthe module.
 6. A method of assembling an energy-efficient modularbuilding, the method comprising assembling a plurality of buildingmodules including a plurality of outer building modules each of theouter building modules including at least one exterior face having aportion of an envelope as a component of the exterior face, the buildingmodules, when assembled forming a structure having the envelope on theexterior faces thereof and having inter-module gaps in the envelope,patching the inter-module gaps with an envelope patch, and sealing allremaining perforations in the envelope with an energy-conserving airexchanger and ventilator to yield the energy-efficient modular building.7. The method of claim 6, wherein at least some heat-conservingapparatus are selected from the group consisting of a window, a door,and an energy-conserving air exchanger and ventilator.
 8. The method ofclaim 7, wherein at least one heat-conserving apparatus is an energyconserving air exchanger and ventilator.
 9. The method of claim 6,further comprising installing within the building an energy monitoringsystem for monitoring of energy use within the assembled building. 10.The method of claim 6, wherein at least some of the building modules areassembled at a site more than 100 yards distant from the site of thebuilding.
 11. The method of claim 10, wherein each distantly-assembledbuilding module has shipping dimensions wherein its height is notgreater than 12 feet, its length is not greater than 70 feet, and itswidth is not greater than 16 feet.
 12. A building made by the method ofclaim 6.